Expansible chamber motor



March 26, 1940. P. D. CORNELIUS 2,195,208

EXPANS IBLE CHAMBER MOTOR Original Filed Sept. 14, 1937 Invenior: 45 PauZ Z7. (brzzeZiua:

44 el -K 1 tendant.

Patented Mar. 26, 194i) EXPANSIBLE CHAMBER MOTOR Paul D. Cornelius, Tulsa, Okla., assignor to Sullivan Machinery Company, a corporation of Massachusetts Continuation of application Serial No. 163,815,

September 14, 1937.

This application August 8, 1939, Serial No. 289,009

.14 Claims. (Cl. 121-150) This application is a continuation of my application Serial No. 163,815, filed- September 14, 1937,, for Expansible chamber motor.

: .My .invention relates to expansible chamber motors, and more particularly to expansible chamber motors which are especially adapted to actuate reciprocating pumps.

In some oil fields mechanical pumping is necessary in order to enable the recovery of a substantial quantity of the oil which is available in the formation but which'will not flow to the surface. due to the fact that the'formation pressure is inadequate to produce anatural flow. To effeet the mechanical pumping of this oil, pumps are arranged in the wells, and these may be operated through a sucker rod line by means of steam or pneumatically operated single-acting pumping motors. Such a system is very eflicient and successful, and employs, usually, groups of pumping motors for pumping a series of reasonably closely adjacent wells, with a central source of operating pressure fluid supply, and'such systems may ordinarily be managed by a single at- However, this makes it necessary that 1 It is an-object of the present invention to pro-I vide an improved expansible chamber m0tor. It is another object of my invention to provide an improved expansible chamber motor having. improved fluid distributing means. It is a further object'of the inventionto provide an improved expansible chamber motor-having a simple distributing valve'structure which is very positive in its movements and certainly held in the different working positions thereof. other'object of the invention to providean im-v proved pumping motor having an improved distributing system in which a single valve controls both admission and exhaust functions and in i which small controlling valve elements moving with or positively actuated by the main distributing valve may be avoided. Other objects and advantages of my invention will hereinafter more fully appear.

. In vtheaccompanying drawing,- in which, for purposes of illustration, one embodiment which the invention may assume in practice is shown: Fig.1 is a side elevation of a pumping motor in It is still anwhich my invention is embodied in an illustrative-form. Y Fig. 2 is a central. vertical section through the lower end of the pump motor cylinder and through the distributing valve mechanism, on a plane corresponding to the line 22 of Fig. 1. Fig. 3' is an enlarged view on asimilar plane to that of Fig. 2, through the upper end of the distributing valve mechanism, showing the dis-v tributing valve proper in a different, to wit, its raised, position. i I

Referring to the drawing, and'first toFig. 1, it will be observed that suitable supporting means, ofwhich a fragment is shown at 2, carries a "motor device 3, which comprises an upper head member 4, a lower head member 5, and a cylinder-shell 6' which may be formed in one or more sections, as desired. The cylinder 6 has a bore 1- in whicha piston 8 is mounted for reciprocation, a nd a pistonrod 9 is adapted to connect the piston 3 to a suitable pump rod orsucker rod line. The pistonfl is single-acting and is adapted to make its working strokes in an upward "direction, under the-action of pressure fluid admitted beneath the same, and to be moved downwardly 25 upon a reduction in the pressure beneath it,' by the weight of the pump rod line, its ownweight, etc- The lower cylinder head 5 is connected. to the upper. head 4 by a series of tie rod devices CH1, and, provides a valve chest and supply and discharge connection arrangement, generally designated l2. A motive fluid supply space I3 has j fluid supplied to it through a supply connection M. An exhaust space It: is spaced materially below the supply space l3 and is connected with an-exhaust connection It. Fluid supply may advantageously be at a pressure of from'two to threehundred pounds per square inch, although it-will be appreciated that a very wide range of operating pressures is possible, depending upon the dimensions of the motor, the depth from which the oil is to be raised, the size of the pump, etc. .The' exhaust connection is maintained by suitable means, not shown, under a back pressure, which, for operating pressures'of from two to three hundred pounds, may well be from fifty to one hundred pounds per square inch; the back pressure used'also depending upon-the operating' conditions, and particularly upon the .depth of the well, the weight of the sucker rod line, etc. Between the supply space l3 andexhaust space Iii is a space I! from which a connection l8 leads to the lower end of the bore of the cylinder 6. The supply space I3. and. the cylinder connected space I! have between them a ll.

PAT 1'=.1-1'1v OFFICE. v

' certain of the stepped bores. I position by screws 33, has a reduced portion 3| septum l3, and a septum 23 separates the cylinder connected space I! from the exhaust space. I5. A suitable valve-chamber-forming element 2|, having a stepped peripheral surface, is

mounted in a series of bores of progressively decreasing size, -22, 23, 24, 25 and 26, and is provided with suitable shoulders, identified by primed numbers corresponding to those which identify the several bores at the bottoms of which said shoulders lie, said several shoulders adapted to seat upon correspondingly numbered but double primed supporting surfacesfor, preferably, upon intermediate gaskets 28 at the junctions of A head 29, held in the member 2! and a passage 35 in the head 23, with the space within the bore 32 at the bottom of the latter. The bore 32 is connected by ports, respectively numbered 36, '31 and 38, with the supply space I3, the cylinder connected space I1, and the exhaust connected space l5. The valve chest member 2! is provided, in its upper end, with an elongated, larger bore .39 coaxial with the. bore 32 and opening through the upper end of the valve chest member. An upper head 43 is held in any suitable manner, as by screws 4!, in a position to close the upper end of the bore 39. Herein, the screws 4| also hold, through the head 43, the member 2| in position. Within the bores 32, 33 there is reciprocably mounted a distributing'valve element 43, which may desirably be made of relatively light material and hollowed out to reduce its weight. ber comprises a lower, suitably ringed or otherwise packed head 44 fitting thebore 32, an intermediate elongated, ringed portion 45, also fitting the bore 32, and an elongated enlarged portion 43 fitting thebore 39 and ringed, as at 41, at its upper end. The head 44 is designed to uncover the .port 38 at its upper end when the valve 43 is in its bottomv position and to cover port 38 when the valve 43 is in its extreme upper position. The portions 44 and 45 are separated by a reduced portion 48 to provide a fluid conducting groove 49, which is adapted, in the position of the parts shown in Fig. 2, to connect the 7 cylinder bore 1, in the portion of the latter beneath the'piston 8, with the exhaust space [5, through the ports 3'! and 38; and which is adapted, in an opposite position of the valve 43 to connect the supply space I3, through the ports 36. and 31, with, the cylinder-connected passage l8. Any suitable means may be provided, if desired, for example small stop portions 5! and 52, for preventing the valve element 43 from moving into such contact with the heads 29 and 40 that the motive fluid will not be able efi'ectually to act upon its opposite extreme ends.

The valve chest member 2i is connected, respectively at and near its upper end, with the cylinder bore 7 at points spaced widely longitudinally of the latter. A conduit 55 connects ,a

port 56, opening through the side wall of the.

chamber 2|, .in a position uncovered when the valve 43 is in bottom position and covered when the valve 43 is in top position, to a point of communication 5Twith the cylinder bore, so located that it is uncovered by the upper end of the downwardly moving piston B only as the latter nears the desired lower limit of its travel and is uncov-.

This memnection 33.

ered by the upwardly moving piston 8 comparatively early in the working stroke of the latter. Another cylinder connection 59 leads from a connection point. 63 comparatively high up in the working portions of the cylinder bore 1, to a port 6i formed in and opening through the top of the valve chest head 40. 'A spring seated check valve 52, opening towards the top of the valve chest, normally prevents flow from the valve chest towards the cylinder bore, but permits flowof pressure fluid through the connection 5'3 from the cylinder bore to the space within the top of bore '39 when the motor piston 8 moves above the point of communication 53. The

- top of the cylinder bore 7 is connected, through a suitable breather device 63, with the atmosphere. A vent port 64 communicates with the bore 33 at the lowermost portion of the latter,

and bleeds oif any pressure which may leak past the rings in either direction along the valve member 43.. l

Asummaryof some of the features which have been mentioned is now in order. The port 58 is sealed by a lateral surface of the valve element 43 when said valve element is in the position shown in Fig. ,3, butcommunicates freely with the space above the top of the valve member. 43 when said, member is in the position shown in Fig. 2. The space within the bore 39 above the valve member 43 may receive pressure from the cylinder bore 7 when thepiston 8 passes above the point of connection 60, but discharge of pressure in the opposite direction through the connection 53 is precluded by the check valve device 32. The lower end of the valve element 43 is subjected to those pressure conditions which exist at any given moment in the lower end of the bore 32, below the valve head 44. Accordingly, the pressure below the valve 43 is never lower than back pressure, and, during the period of admission to the motor cylinder 1, is'equal to the working cylinder pressure. This obviously is advantageous because initial upward shifting of the valve member 43 is effected bymotor back pressure when-the pressure upon the top of. the valve 43 is reduced to atmospheric, but during the working stroke of the motor piston the valve 43 is held more strongly,and also in more fully elevated position, bythe cylinder working pressure. Of course, the latter feature is a matter of the design.

Now,'the mode of operation of theinvention will be clearly understood. Assuming the parts to be in the. position shown in Fig. 2, with the motor piston 8 still moving downwardly and with the distributing valve .43 in the position to connect, the cylinder, through port l8, space. H, ports 31, groove 49, ports 38, and space I5, to the exhaust line, it will beappreciated that when the piston 3 moves down below the connection point 51, the connection 55 and port 56 will be effective to permit the escape of the pressure, which has prevailed upon the top end of the dis.- tributing valve 43, through the bore 7 of the cylinder 6 and to atmosphere through the con- Thereupon, since motor back pressure will still prevail in the space below the'head 44 of the distributing valve 43, valve 43 will be moved upward to a position in-Which it will occlude the valve chest end of the port 58, cover the port 38' opening into the exhaust space l5, and establish. a condition for the admission of motive fluid tothe lower. end of the cylinder bore 1, from the space 13 through the ports v36, the groove 43, 'the ports 37., and cylinder-connected space l1, and "passage l8, openinginto' the bottom of-the cylinder bore 1. Ofcourse, as soon as line pressure attains to the space H, it will also attain, through the passage 33, port 34, and v passage '35, to the bottom of the distributing valve 43, and force the latter still further up in its valve chest, and hold it firmly in elevated position tmtil suchtime as a changed relationship of. the parts shall serve to create a condition in which the product of the-'pressureupon the top head of the valve 43 and the area of that head shall exceed the product of cylinder working pressure and the area of the lower head 44 of the distributing valve 43. It will be noted 1 that the side of the valve head 44 continues to cover the port 33 whenthe valve 43 is in'its extreme upper position and that the lower end of valve 43 is subjected only to supply line pressure When the piston 8 in its =upwardmovement passesabove the connection point 51, motive fluid from; the cylinderbore will attain tothe connection 55 and port 55, but will not be admitted to act upon the upper end of thedis- I tributing valve because the port 56 will be sealed 7 by the lateral walls of the head 46, and the packing 41 will preclude leakage of fluid along the portion 45 of the valve 43 and into the'space above the distributing valve in sufficient quantity i to cause the latter to move downwardly. I

When the piston 8 in its continued upward movement passes above the point of connection Gil-a point which it reaches as it approaches the desired upper limitof its working stroke f cylinder working pressure will pass through the connection 59, past the check valve tZQand;v through the port 6 l and acton the larger, upper end area of the valve 43 and force that valve back-down to the position shown in Fig. 2. Of

course this will occasion a prompt reduction in the pressure beneath the piston 8, and the latter will commence its downward travel under its own Weight and that of the parts which it supports. The reduced pressure will act, through the conduit 55 and passage 56, upon the top of the valve 43, so that the valve will not move from I phere. However, the check valve 62 precludes the venting of the pressure acting on the top of the distributing valve until after the top of the piston 8 passes below the cylinder end of passage 55, and'then the pressure acting upon the top of the distributing valve will be vented'through the port 56, passage 55, cylinder bore 1, and valve 83, to the atmosphere, and the valve. 43 will again be raised to the position shown in Fig. 3 by the rnotor'back pressure acting upon its lower end; and the cycle of the motor will be repeated.

' It will be evident that I have provided a very simple distributing valve mechanism-one which is adapted to control through a single valve,

both the admission and exhaust functions for a single-acting motor, and in which thedistributin'g valve is positively held in admissionefiecting" and also exhaust-elfecting position. It will be evident that the only auxiliary valve mechanism associated with the distributing. valve fis'a single; simple, spring-pressed check- Of course, if it were not for the valve, which is caused to unseat during each cyg cleof the motor piston. It will be apparent that no auxiliary valve devices are either positively moved by or with the distributing valve during the movements of the latter. It will be noted that the construction is simple, rugged,

and positive in action, and well adapted to the" functions it is designed to perform.

" While I have in this application specifically described one form which my invention may assume in practice, it will be understood that this form is shown for purposes of illustration and that the invention may be modified and em bodied in various other forms without departing from its spirit or the scope of the appended claims. I,

What I claim as new and desire to secure by Letters Patent is: i

1. In a motor, in combination, a'cylinder having a bore and means for venting one end thereof continuously during normal motor operation, a piston reciprocable in said cylinder, and valve mechanism for said motor including valve and controlling means therefor including means providing a pressure chamber and'mleans movable in the latter having a pressure area acting when subjected to cylinder working pressure to move said valve, and means for controlling the supply of such-pressureto said area and the venting of such pressure therefrom including a pair 01'' con.-

duits having their extremities remote from said area opening into communication with the cylinder bore at points widely spaced longitudinally of the latter but both covered and also uncovered by each end ofthe piston during each complete cycle oirpiston movement and one of which has its other extremity opening laterally into said pressure chamber while the other has communication with said pressure chamber through the endof the latter. I

' 251:1 a motor, in combination, a cylinder hav' ing a bore and means for venting one end thereof continuously during normal motor operation, a piston reciprocable in said cylinder, and valve mechanism for said motor including a valve and controlling means therefor "including means providing'a pressure chamber and means ntovable in the latter having a pressure area acting when subjected to cylinder working pressure to move said valve, and meansi'or controlling the supply of such pressure to said area and the venting of such pressure therefrom including a pair of conduits having their extremities remote, from said area opening into communication with the cylinder bore at points widely spaced longitudinally of the latter but both covered and also uncovered by each end of the piston during each completecycle of piston movement, and the one of said conduits whose extremity already mentioned is the first to be overrun by said piston during the working stroke of the latter, opens at its other extremity into said pressure chamber at'a point nearer the valve than does the other extremity of the other of said conduits. 1 3. In a motor, in combination, a cylinder having a bore and means for venting one end thereply ofsuch pressureto said area andthe venting of such pressure therefrom including conduits having their extremities remote from said area opening into communication with, the cylinder boreat points widely spaced longitudinally of the latter but. both covered and also uncovered by each end of the piston during each complete cycle of piston movement, the opposite extremities of said conduits one having a check-valved and the other a free opening into said pressure chamber, one of said openings entering said chamber laterally.

4. In a motor, in combination, a cylinder hav ing a bore and means for venting one end thereof continuously during normal motor operation, a piston reciprocable in said cylinder, and valve mechanism for said motor includinga valve and controlling means. therefor including means providing a pressure chamber and means movable in the latter having, a pressure area acting when subjected to cylinder Working pressure to move said valve, and means for controlling the supply of such pressure to said area and the venting of such pressure therefrom including conduits hav ing. their extremities remote from said area opening into communication with the cylinder bore at points widely spaced longitudinally of the latter but bothcovered and also uncovered by each end of the piston during each complete cycle of piston movement, the oppositeextremities of said conduits one having a check-valved and the other a free opening into said pressure chamber, the former into the end of said chamber and the latter into the side thereof.

5. 'In a single-acting motor, in combination, a cylinder having a bore, a piston in said bore, and fluid distribution means for effecting ad'- mission and exhaust relative to the working end of said cylinder including a valve and means for eiiecting reversals of valve position including oppositely facing areas, means for subject ing one of said areas to a pressure efiective to move said valve in one direct'ion'when the other of said areas has the pressure vented therefrom, and means for supplying pressure to and vent ing pressure from said latter area including passage means having communication with the cylinder bore at points widely spaced longitudi nally of the cylinder and having communication, through ports extending respectively in the same direction as and perpendicular to the axis of valve movement, with said latter area.

6. A motor of the kind comprising a cylinder vented at one end and having a piston reciprocable therein, and valve mechanism controlling the movement of the piston and including a valve having associated therewith oppositely directed pressure areas adapted to be subjected respectively to pressures acting in opposite direc tions by which the movements of the valve are controlled, the pressure area directed in one direction being connected at all times with the other end of said cylinder, and the pressure area directed in theopposite direction being connected by control connections respectively with the space within the cylinder toward opposite ends thereof, whereby during the reciprocation of the piston it is connected during each cycle of the latter to the working pressure in said cylinder and to the vented space in the cylinder. v

'7. A. motor of the kind comprising a cylinder vented at one end and having a piston reciprocable therein, and valve mechanism controlling the movement of the piston and including a valve, having associated therewith oppositely directed pressure areas, adapted to be subjected respectively to pressures, acting in opposite'directionsby which the movements of the valve are controlled, the pressure area directed in one direction being connected at all times with the other end of said cylinder, and the pressure area directed in the opposite direction being connected by control connections respectively with the space within the cylinder toward opposite ends thereof, whereby during the reciprocation ofthe piston it is connected during each cycle of I the latter to the working pressure in said cylinder, to cylinder back pressure, and to the vented space in the cylinder.

8., In a motor, in combination, a cylinder, a piston reciprocable therein, a valve mechanism for said motor including, a valve and controlling means therefor having a pressure area acting to move said valve, and means for supplying pressure to said area and venting pressure therefrom including conduits, of which one contains a check valve, respectively having their extremities remote from said area opening into communication with the cylinder bore at points Widely spaced longitudinally of the latter and both covered and also uncovered by each end of the motor piston during each complete cycle of piston movement, and one of said conduits cntrolled by a lateral surface of said valve.

9. In a motor, in combination, a cylinder continuously vented at one end during normal motor operation, a piston reciprocable therein, and valve mechanism for said motor including a valve controlling theseveral functions of the motor cycle and having a pressure area acting to move said valve in one direction and means for subjecting said area to the pressure conditions in the working space'of said cylinder, and another pressure area acting to move said valve in an opposite direction, and means for supplying pressure to said latter area and venting pressure therefrom including conduits respectively having their extremities remote from said area opening into communication with the cylinder bore at points Widely spaced longitudinally and both covered and, also uncovered by each end of the piston during each complete cycle of piston movement.

, 10. In a single acting motor, in combination, a cylinder continuously vented at one end during normal motor operation, a piston reciprocable therein, and valve mechanism for said motor including a valve and controlling means therefor having a pressure area for moving the same into admission-effecting position, and associated means for subjecting said area to a relatively low throwing pressure and subsequently to a higher holding pressure.

,means for subjecting said area to a relatively low throwing pressure and subsequently as a result of its own movement, to a higher holding pressure.

12. In a distributing valve mechanism for a motor cylinder, a valve chest, fluid supply, exhaust and cylinder connections leading thereto,

said exhaust connection maintained during motor operation under a substantial superatmosphericpressure, a valve in said chest, controlling means for said valve including a pressure area for moving the same into admission-effecting position, and means for subjecting said area to exhaust pressure, to throw said valve, and on predetermined movement of said valve to fluid vented end of the cylinder supply pressure, to hold said valve in the position to which it is moved.

13. A motor of the kind comprising a cylinder vented at one end and having a piston reciprocabletherein, and valve mechanism controlling the movement of the piston and including a valve having associated therewith oppositely directed pressure areas, means for subjecting one of said areas continuously to the pressure conditions 1n the working end of said cylinder, and means for subjecting the other of said areas throughout the greater portions of the opposite passes of the motor piston respectively to the pressure in the and to a higher pressure.

a cylinder'continuously vented at one end during 14. In a single acting motor. in combination,

normal motor operation, a piston reciprocable. therein,and valve mechanism for said motor ineluding a valve controlling the several functions means for continuously subjecting said area to the pressure conditions in the working space of said cylinder, and another pressure area acting to move said valve in an opposite direction, and means controlled by said motor pistonfor sup plying pressure to said latter area and venting pressure therefrom during each completecycle of piston movement. v

- PAUL D; CORNELIUS. 

